FIG. 13 is a bottom view of an example of conventional LED module (see Patent Document 1, for example). The LED module X illustrated in the figure includes an LED chip 91, a resin package 92, and two leads 93A and 93B. The two leads 93A and 93B are spaced apart in direction x, and each of the two leads is partially covered with the resin package 92. The LED chip 91 is the light source of the LED module X and mounted on the lead 93A. Of the two leads 93A and 93B, the portions bent to be positioned on the bottom surface side of the resin package 92 constitute mounting terminals 94A and 94B, which are used for surface-mounting the LED module X.
The surface-mounting of the LED module X on e.g. a circuit board (not shown) is often performed by a reflow process. In this process, with the mounting terminals 94A and 94B provisionally bonded to a wiring pattern of the circuit board via solder paste, the temperature in the reflow furnace is raised to melt the solder paste. In this process, when the surface tension of the molten solder paste adhering to the mounting terminal 94A and the mounting terminal 94B do not balance each other, the LED module X may move from a proper position on the circuit board.
Patent Document 1: JP-A-2007-329516